As a method of forming a fine pattern on a semiconductor substrate or a metal substrate, heretofore, photolithography which comprises applying a photosensitive resin to a substrate, forming a pattern by light exposure via a mask, and etching the substrate using the photosensitive resin as a mask has been employed.
However, photolithography has problems in that its process is complicated, and an exposure apparatus and the like are very expensive, thus increasing the cost. Further, if there is a distortion or a fine protrusion on the substrate, the resolution will not be high due to the problem of the depth of focus and as a result, the pattern formation accuracy is highly problematic.
Therefore, as a method to form a fine pattern at a low cost by the contact process, an imprinting method has been disclosed (for example, Patent Document 1). The imprinting method is a technique of pressing a mold having a desired pattern against a resin material applied to a substrate to form a desired pattern on the resin on the substrate. As the imprinting method, a thermal imprinting method of forming a pattern by heat using a thermosetting resin and a photoimprinting method of forming a pattern by light irradiation using a photocurable resin have been known.
Particularly, the photoimprinting method attracts attention in recent years, since a pattern can be formed at low temperature under low pressure, whereby no heating and cooling processes are necessary, and a high throughput can be expected (Non-Patent Documents 1 and 2). As the photocurable resin to be used for photoimprinting, PAK-01 manufactured by Toyo Gosei Co., Ltd. has been known (Non-Patent Document 3).
Further, as a method of processing a fine pattern on a substrate, a dry etching method may be mentioned, and in a case where a substrate is processed using a photoimprinting method, since a photocurable resin is used as a resist mask at the time of etching, the etching resistance is required. Patent Document 2 discloses an example of improvement in the etching resistance by incorporating an acrylic monomer having a cyclic structure.